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Hi, I'm Dave. I'd be glad to try and help shed some light on the situation
Rheem service manuals are hard to come by, I can tell you that one scenario you could have, is too high of an ambient temp. the condensing unit becomes the evaporator in heat mode, which means that the ambient temp is driving your suction pressure WAY too high (as evidenced by the nearly identical suction and discharge pressures you've listed) it cold be that the compressor is trying to create a viable compression ratio, working too hard and tripping on the internal overload or some other safety. Another situation you could be getting here is a failed/malfunctioning reversing valve, or check valve. the valve that re-directs refrigerant flow in heat mode is the reversing valve. the valves that keep the refrigerant from flowing the wrong direction are check valves. if any of these are malfunctioning, it would cause the head that the compressor is creating, to be pushed into both sides of the system. which would also give you identical pressures. one suggestion would be to lightly spray the condensing unit's coil with water while it is running. if the suction drops to about one third of the head (or thereabouts) it's likely that the ambient temp is too high to be running the unit in heat mode. if both the head and suction drop, and remain pretty much the same as each other, you likely have a failing/failed valve, and will need further troubleshooting.
Thanks for your analysis of the situation. I figured that the problem was probably in the reversing valve. Also, given that the unit shutsdown after 1-1/2 minutes makes me think that a sensor/check valve is kicking in. I will execute the test you recommended to determine if the ambient air is too high and report back to you. Is there any way to further test the reversing valve or to find out what check valves/sensors may exist in this unit?
Hello , let me see if I can guide you here. First is the cause is th eoutdoor temperature thi sunit has a hi presure switch and th eboard will flash a code. Since yo ulisted Led 1 is off and Led 2 is on thi smeans you tripped on a low pressure lock out. It will auto reset three times then tuwning the power on and off or touching the test pins will reset.
Low pressur elock out typicall mean low charge so you may have a leak. The only way to know here is to put a set of guages on it. Now since it seemed to work in Cool mode you may also have a failed TXV on the outdoor unit. In the cool mode it is bypassed with an internal check valve in the heat mode it is metered. Again a set of guages will tel us what the system pressures are.
TXV can fail for many reason from a bad power head to poor installation. If an old line set was used and not flushed correclty or lack of a drier filter , or not running nitrogen through the lines during the brazing process can all be causes.
Let me know if I can be of more help thank you Richard
Hello also if you need a manual let me know I will send you a link.
Thank you Richard
Hello sorry there was a long delay in the message.
Let me see if I can answer all your questions. First even though you cool ok you can have a system issue. An over charged system will work fine in cool however one it is switched to heat refrigerant has to be taken out of the system by a charge compensator . On this model it will look like a big black can. If it is over charged the compensator can not remove enough so the head pressure goes up and trips the sensor. You have hi and low pressure sensor on this model.
To correct this issue it is simple first someone needs to check, measure and set the air flow to be close to 400 CFM per ton of cooling. You have 3 ton so 1200 CFM once the do this set to cool , they take the system running pressure convert them to saturation temps and subtract the temps of the lines. This gives them Super Heat and Sub cooling. Super Heat should be between 10 and 15 Sub cooling 10 degrees.on this unit. Then switch to heat mode. to check. The system should run fine with outdoor temp 80 and indoor temp 80 if it is hotter than that you will have to wait for a good test since the head pressure will naturally be hi at those temps.
The reversing valve on Rheem and Ruud is energized in heat mode. So ( it is not easy to access on the 13PJ series but there is a blue wire that comes from the thermostat un hook it while in the heat mode and it will shift to cool you will hear it to know it is shifting. Or if someone can access the valve get a couple of small earth magnets ( radio shack) place them on the brass body unit the stick then when the valve shifts you will see them move. ( there is probably a video in you tube somewhere lol ) .
To check the sensor look for them they small with two wires ( probably yellow and brown) pull one of the wires off where is goes to the board and the unit will shut down proving the switch will open.
Let me know if you need more. Ill look for your response.
Can you send me the service manual you referenced in your email.
Let me know if these links work if not I can try a differant way thank you Richard
These look similar to the installation manuals that came with the AH and Heat Pump, though I think these might be more detailed. I hope so.
It rained all weekend so I was not able to troubleshoot the system.
I will get back to you this week with what I discover.
thanks for the help.
These are all they offer in the way of technical documents. They stopped making service manuals a few years ago. Once the unit has a code ( flash code) then you can use that as a guide to troubleshoot the system. Pay close attention to the flash code and remember it is a guide not a diagnostic tool. Example if the Low pressure switch tripped you may have a dirty filter, low charge, low airflow or stopped fan. It does not mean the low pressure switch has failed. However, parts chage on some ofthe older models they used a 50 PSI low pressure switch this had a common issue of tripping for no real reason so they switched to a 15 PSI pressure switch. First steps to make sure the system was set up correctly Air Flow number 1 , 400 CFM per ton of cooling if this is wrong all measurement will be wrong. Then super heat and sub cooling for this you need system pressures and line temps. Then we can see how the system is doing.